In what may be the first good news in the battle against obesity among Americas children, federal researchers report that the latest data suggest that the number of overweight kids may be leveling off. However, experts caution theres still much to be done to improve the health of American children because the number of youngsters who are overweight today is still triple what it was in the 1960s and 1970s.

The rates are still very high. But this study suggests there may be some cause for optimism, as the rate appears fairly level over eight years, said study author Cynthia Ogden, an epidemiologist at the National Center for Health Statistics, whose findings are published in the May 28 issue of the Journal of the American Medical Association.

Others agreed with Ogdens assessment.

After 25 years of extraordinarily bad news about childhood obesity, there is a glimmer of hope. But its much too soon to know whether rates have truly leveled off, said the author of an accompanying editorial in the same issue of the journal, Dr. David Ludwig, director of the Optimal Weight for Life program at Childrens Hospital Boston. Even if they have leveled off, the prevalence is at such high levels that unless we do something, unless we redouble our efforts, this generation is in store for a shorter and less healthful life than their parents.

Using height and weight data from the US National Health and Nutrition Examination Survey (NHANES), the researchers calculated the body-mass index (BMI) for 8,165 American children between the ages of two and 19. The data used for the study was collected in 2003-2004 and again in 2005-2006.

The researchers found no statistical difference between the two time periods, and so combined them into one. Between 2003 and 2006, 31.9% of American children had a BMI higher than the 85th percentile for their gender and age. A BMI above the 85th percentile means a child is at risk of being overweight.

Slightly more than 16% of the children had a BMI at or above the 95th percentile, indicating they were overweight. And 11.3% had a BMI at or above the 97th percentile, indicating these kids were significantly overweight.

When the researchers compared this data to data from as far back as 1999, they found no statistically significant differences in the prevalence of overweight children.

The researchers did find that Mexican-American girls and boys as well as non-Hispanic black girls were more likely to have a high BMI than non-Hispanic whites. But Ogden said that, although these levels still remained high, they also appeared to have leveled off.

The study didnt look at factors that might be contributing to the trend, according to Ogden.

Ludwig said the numbers may have something to do with all the attention that has been paid to the problem of childhood obesity. But, he added, there still needs to be much more focus given to the problem at a national level.

We need a comprehensive national strategy. We need to regulate junk food ads to kids, we need better school lunch funding, better funding for regular physical education in schools and after-school activities, and we need improved insurance reimbursement for obesity prevention and treatment services, he said.

Its much too soon to tell if theres a true plateau or if this is just a temporary lull. Without major declines in prevalence, the health toll will continue to mount, Ludwig said.